I was looking at aftermarket diverter valves and was wondering if others have done this upgrade. Did you feel a difference in performance and whose did you use. I am looking at Evolution Motorsports billet valves.

 

Absolute waste of money. They don't give you any performance benefits, and mine failed after about a year causing a raft of other problems. Put the originals back in after much troubleshooting and money wasted, and all problems corrected themselves (including spark plugs). Don't do it.

 

I have the Evoms billet valves which were installed as part of their 775 kit and motor build but I'm not sure what performance improvements you would expect to see just installing the valves without a tune and/or improvements to turbos, IC's, etc. All they do is provide a blow-off capability to protect motor, turbos, etc. when ECU programmed boost parameters are exceeded. While that's very important, the oem ones are fine if your car is basically stock. Once you start making "significant" max boost, then you need something more robust like the Evoms units. Hope that's helpful.

 

+1....waste of time, effort, money. I put on Forge billet alum piston type. Car was acting odd...started testing items...took DV's off and noticed one was stuck...after just a few months! Luckily it stuck partially open or I guess I could have exploded my turbocharger?? Put OEMs on....and runs fine...holds boost. Only difference I noticed with aftermarket was sounded a little different....

I would pass!

Good luck...
DC

 

Seems like a waste to me. I installed some and my peak boost levels went down quite a bit. I have seen claims that boost builds sooner but I can't see how the valves would have anything to do with that.

 

I also installed Forge (metal) as a precursor to revamping my ECU. By themselves they will not improve a stock engine's output or performance. If you intend to leave your TT stock don't waste your $$$. They may be required if you reach 700hp and even then the OEM's (plastic) may still be okay. I fell for the same hype but I've gotten a lot smarter since then, they really aren't necessary. BTW, mine seem to be working fine, at least for now.

 

Diverter valves (also more commonly called blow off valves) open when you let off the throttle to evacuate pressure from the intake system. Without them air will slam into your throttle body, and come back to the turbos which can cause bearing damage in the turbos among other things.

They do nothing to add power.

I'll say it again, they do nothing to add power.

In the 996 cars the factory diverter valves were known to leak at higher boost, even when they were closed. A lot of people like to replace them.

The 997 parts don't have this problem and there isn't really any reason why you should replace them. If you *really* want to spend money on something, buy a set of injectors and 5 bar FPR from Protomotive and run E85.

 

Thanks guys I was going to upgrade the IC, tune and I figured the upgrade was cheap and might help out.

 

Leave em'. I ran the evoms. They just caused problems.

 

I am looking for the OEM diverter partnumber. I can not find these valves in the Porsche PET.
Thanks, K.

 

That part number is like the Loch Ness monster, or Sasquatch...Been sighted, but not sure it is real

The VTG on the car is made by Borg Warner and if you look at this link, you should be able to get what you need. I have had no luck either looking in PET or anywhere else?? This appears to be the part ...BorgWarner 179424

DC

https://www.google.com/search?q=Borg...e+Kit&tbm=shop

 

Good find Rock (once again!). What would you notice if your oem diverters were "worn out"? Is it an easy diy while the turbos are on the car?

 

Hi Rocks,

thanks for this info. I got a P0299 on my 997.1TT and I think this is related to my problem.

I was confused by reading some stuff here. I think I did not understand, that the 996TT valves are different on a 997.1TT. (see picture)
So on the 997.1 they are direct mounted on the Vtg turbo. Correct?
Is it possible to change this valves (aftermarket or OEM) without removing the exhaust part?

Thanks again.
K.

https://www.6speedonline.com/forums/...ation-how.html

 

Hi there,

First, just want to point out that the OEM DV's/BRV's have been holding up great on these cars and typically do not cause issues in general.

That said, if you do have an issue it would likely manifest like/as a boost leak. You would likely not reach your expected boost level(s) and/or would not hold the boost level.

As you can see, they do have a rubber diaphram and spring, so certainly subject to wear over time.

This is a fairly easy, straightforward DIY. And would usually just need to jack up the car and remove wheel aprons for easy access. 1 or two of the bolts (3 each side) are a little tricky to get to, but nothing difficult at all. Definitely no need to take Turbos off the car for this.

If I can find some pics I may post up more later.

Good luck.
DC

 

Hi,

Yes, you are correct. The 996 and 997 TT are different.

See my post above. These are fairly easy to change/replace. And they are mounted right in to the cool side Turbocharger housing with 3 hex head bolts.

Also, to be clear I THINK that part above should fit...but have not verified part number, etc..

Good luck.
Dc